It is known that triforine exhibits very effective fungitoxic and acaricidal properties, and that these properties unfold in a particularly advantageous manner when triforine is incorporated as the active ingredient into certain liquid compositions.
U.S. Pat. No. 3,696,106 and German Offenlegungsschrift No. 2,128,225 disclose triforine, as well as fungitoxic, liquid emulsion concentrates containing triforine as the active ingredient. A particular characteristic of those liquid compositions is that they contain dimethylformamide and N-methyl-pyrrolidone as the solvent medium, and the isopropylamine salt or the triethanolamine salt of dodecylbenzenesulfonic acid as the emulsifier. Such emulsion concentrates form, upon dilution with water, highly effective liquid plant protection compositions, but they have the disadvantage that the active ingredient, triforine, has only a limited stability therein. Especially at higher temperatures, but even at only moderately elevated temperatures of about 20.degree. C., the triforine undergoes a noticeable degradation, so that such liquid emulsion concentrate compositions have a relatively short shelf-life under normal conditions or must be stored under special, cost-increasing conditions.
While it is possible to improve the storage stability of liquid emulsion concentrate compositions containing triforine, such as those above referred to, by using a nonionic emulsifier, this modification introduces other significant disadvantages, such as inadequate solubility of the triforine, weaker biological activity and/or inferior spray properties.